CVE-2021-39255: Buffer Overflow

Published Sep 6, 2021
·
Updated

A crafted NTFS image can trigger an out-of-bounds read, caused by an invalid attribute in ntfsattrfindinattrdef, in NTFS-3G < 2021.8.22.

Other sources

From https://www.openwall.com/lists/oss-security/2021/08/30/1:

Security vulnerabilities were identified in the open source NTFS-3G and NTFSPROGS software. These vulnerabilities were confirmed and resolved. To our knowledge, these vulnerabilities have not been exploited.

These vulnerabilities may allow an attacker using a maliciously crafted NTFS-formatted image file or external storage to potentially execute arbitrary privileged code, if the attacker has either local access and the ntfs-3g binary is setuid root, or if the attacker has physical access to an external port to a computer which is configured to run the ntfs-3g binary or one of the ntfsprogs tools when the external storage is plugged into the computer. These vulnerabilities result from incorrect validation of some of the NTFS metadata that could potentially cause buffer overflows, which could be exploited by an attacker. Common ways for attackers to gain physical access to a machine is through social engineering or an evil maid attack on an unattended computer.

We recommend installing and applying the update with the security fixes, and advise to follow security guidance and frameworks such as NIST for assessing and improving an organization’s abilities to prevent, detect, and respond to security threats and cyber attacks.

AFFECTED PRODUCTS: All previous versions of open source NTFS-3G and NTFSPROGS.

WORKAROUND: None

SOLUTION: Upgrade to 2021.8.22

PROJECT URL: https://github.com/tuxera/ntfs-3g

ADVISORY ID: NTFS3G-SA-2021-0001

ISSUE DATE: 2021-08-30

SEVERITY: Moderate

CVEs: CVE-2021-33285, CVE-2021-35269, CVE-2021-35268, CVE-2021-33289, CVE-2021-33286, CVE-2021-35266, CVE-2021-33287, CVE-2021-35267, CVE-2021-39251, CVE-2021-39252, CVE-2021-39253, CVE-2021-39254, CVE-2021-39255, CVE-2021-39256, CVE-2021-39257, CVE-2021-39258, CVE-2021-39259, CVE-2021-39260, CVE-2021-39261, CVE-2021-39262, CVE-2021-39263

CVSS SCORE: 3.9-6.7

ACKNOWLEDGMENT: Jeremy Galindo, Akshay Ajayan, Kyle Zeng and Fish Wang for reporting these vulnerabilities.

Red Hat

Affected Software

6 affected componentsFixes available
redhat/ntfs3g<2021.8.22
2021.8.22
tuxera NTFS-3G<2021.8.22
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
debian/ntfs-3g
1:2017.3.23AR.3-4+deb11u41:2017.3.23AR.3-4+deb11u31:2022.10.3-1+deb12u21:2022.10.3-5

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/ntfs3g to a version that resolves this vulnerability.

    Fixed in 2021.8.22
  2. Upgrade

    Upgrade debian/ntfs-3g to a version that resolves this vulnerability.

    Fixed in 1:2017.3.23AR.3-4+deb11u4Fixed in 1:2017.3.23AR.3-4+deb11u3Fixed in 1:2022.10.3-1+deb12u2Fixed in 1:2022.10.3-5
  3. Upgrade

    Upgrade open source NTFS-3G / NTFSPROGS to a version that resolves this vulnerability.

    Fixed in 2021.8.22Patch NTFS3G-SA-2021-0001

Event History

Sep 7, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via NVD·03:15 PM
DescriptionSeverityWeaknessAffected Software
Dec 2, 2025
Data Sourced
via Debian·09:38 PM
DescriptionAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-39255?

CVE-2021-39255 has a medium severity rating due to the potential for out-of-bounds read vulnerabilities.

2

How do I fix CVE-2021-39255?

To fix CVE-2021-39255, update ntfs-3g to version 2021.8.22 or later.

3

What systems are affected by CVE-2021-39255?

CVE-2021-39255 affects ntfs-3g versions prior to 2021.8.22 on various Linux distributions.

4

What type of vulnerability is CVE-2021-39255?

CVE-2021-39255 is classified as an out-of-bounds read vulnerability.

5

What is the cause of CVE-2021-39255?

CVE-2021-39255 is caused by an invalid attribute in the ntfs_attr_find_in_attrdef function.

Contact

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